There are also "partly electrified" possibility e.g. only 10% of track electrified (stations for example). Trains can recharge batteries or supercapacitators th

There are also "partly electrified" possibility e.g. only 10% of track electrified (stations for example). Trains can recharge batteries or supercapacitators there from wire. There already are such existing light rail lines. [1] https://en.wikipedia.org/wiki/Battery_electric_multiple_unit https://en.wikipedia.org/wiki/Battery_electric_multiple_unit